The glow plug is flashing - what does it signal and is it a concern?

Does the glow plug indicator come on just before starting the engine? No big deal, the car has just informed about the heating of the candles. However, it happens that this element on the dashboard constantly blinks or stays on after you have moved a long time ago. We suggest what the reasons may be.

Shortly speaking

A glow plug indicator can blink while driving for a number of reasons. Most often, this indicates a problem with the injection system (or its control), a clogged fuel filter, damage to the fuel pump, brake lights or turbocharger controller. Alarming symptoms, in addition to the flashing of the warning light, also include a change in the culture of the engine, problems with starting and smoking candles. To avoid serious damage, including even engine failure, have the vehicle repaired immediately.

Why Diesel Glow Plugs?

Ever wondered why glow plugs are essential for starting diesel vehicles? We already explain! In order for the fuel to ignite spontaneously at all, the combustion chamber must be sufficiently heated so that the air drawn into it reaches a temperature of at least 350 degrees Celsius.. The entire heating process lasts from several to several seconds, and is accompanied by an unambiguous signal - a burning candle on the instrument panel. When it goes out, it means that the temperature has reached the required level, and you can turn the key all the way.

When things don't go as planned ...

Does the glow plug indicator keep flashing while driving? They didn't have to be candles. Sometimes they get these symptoms. problems with the injection system or its control. In many cases, finding the problem without connecting the car to the computer in the workshop is almost a miracle. Check with the mechanic that other sensitive components are not defective - turbocharger regulator, high pressure pump, camshaft speed sensor... In the case of cars of the VW group, the diagnosis is additionally complicated. In their case, the problem most often concerns brake lights, so first you should check if the headlights come on at all after turning on.

Other reasons for the blinking of the indicator? Clogged, needs replacement malfunction of the fuel filter or vacuum sensor... Damage is not uncommon either. fuel pump or its pressure regulator.

Another reason for the alarming behavior of the glow plug indicator could be: relay failure... The glow plug controller has a special temperature sensor, thanks to which it can monitor the operation of the spark plugs. If it is damaged, the indicator either does not light up at all, or does not go out for a long time. The most obvious signals include smoking and uneven engine operation, a problem with starting (delayed start, the engine does not respond at all), an error code on the computer. In this case, check items such as relay electrical connections, input voltage and ignition switch.

Driving with broken candles is dangerous

Unfortunately, it also happens that the failure of a glow plug is hidden for a long time. The indicator light on the dashboard remains unchanged, only subtle signals such as deterioration of the culture of the engine (noise, vibration) or light smoke of the spent spark plug at start... Today's Common Rail diesel engines differ from older generations in much greater efficiency. because allow you to start the car at a temperature of 0 degrees, even when one of the candles is out of order... However, modern diesel engines also require close attention. If you ignore the above symptoms (different work culture, smoking) and drive a car with a worn-out spark plug, you risk that this important element will fall apart and fall into the engine cylinder. As a result, the drive will be damaged. This is why we recommend that you check your candles regularly.

How to care for glow plugs?

Glow plugs are worth looking after all year round. How? Above all loosen and tighten them periodically - thanks to this, when they are worn out, I will not have thread sticking, so you can replace them with new ones without much difficulty. You will also reduce the risk of them pulling out, which may require the removal of the cylinder head in a specialized service center, and this costs even several thousand zlotys. For screwing candles always use a torque wrench... But before that, apply a heat-resistant grease to them. Thanks to this, they will not only be easier to loosen in the future, but will also be less susceptible to corrosion and better sealed.

On a daily basis, you can simply watch the glow plugs work. When they are close to burning out, they often take longer to start the car on a cold engine.

And most importantly - when choosing candles for your car, be guided by the manufacturer's recommendations. Buying the same candles that were originally installed in the car, can prevent their damage, as well as suspicious engine operation, spark plug driver failure and increased formation of harmful substances, which in the worst case will lead to costly repairs.

Are you waiting for a spark plug replacement? Go to the "Ignition System" category on avtotachki.com and find the product you need.

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